SilverFast Blog

Scanning heavily scratched negative stripes can be problematic because big scratches and imperfections affect the general exposure and histogram in Negative mode. Especially those dark scratches (white on the negative stripe) can influence in the correct representation of the image.

The next pictures illustrate a possible effect created by a long scratch and a solution to that problem:

Preview scratched negatve

Note the strong blue cast created by the long scratch on the upper half of the image.

The next step is to open the expert mode in the NegaFix window (only Silverfast Ai or Ai Studio).

NegaFix expert mode

The expert dialogue shows a histogram, the scratch is mainly affecting the green and blue channels (towards the left end of the histogram).

This is preventing NegaFix from applying the curve correctly.

To correct this we will reduce the size of the scanning frame as to cover the biggest area of the image not affected by the scratch.

Reducing the scanning frame in SilverFast

After reducing the scanning frame and releasing the mouse button, you will see how SilverFast applies the respective curve to your film.

Reduced scanning frame

But wait!

You are not ready yet, if you resize the scanning frame, you will notice how the blue cast re-appears.

Before you proceed, please go to the NegaFix dialogue and deactivate the checkbox located right above the “Auto tolerance” and to the left of the “Auto” button.

Deactivating auto tolerance

After this step, the Auto tolerance will not work automatically, you can resize the scanning frame to include most of your image now.

Scanning frame resized

Voila!

Your image has been resized and the respective curve applied to your negative, now you can continue to work.